1. Field of the Invention
The present invention relates to a travelling or transverse crane for sea-going ships of any kind.
The invention relates more particularly to a fixed transverse crane with a travelling winch trolley or carriage, particularly a crane of the auxiliary type for handling small cargo such as ships stores and provisions, machinery parts and equipment, luggage, etc.
An object of the invention is to provide a transverse crane of this type having cantilevered beams extendable outside the ship sides such that cargo can be handled from a position along either side of the ship to various positions below the ship deck.
2. Description of the Prior Art
There are known several types of so-called gantry cranes wherein the crane beam or beams supporting a winch trolley or a travelling carriage are provided with a cantilevered beam or beams extended beyond the supporting posts on the ship. There are also known various types of gantry cranes wherein the horizontally extending carrier beam can be retracted from a cantilevered position, and furthermore there are known cantilevered crane beams which are pivotally connected to the carrier beam mounted on the ship.
Although effective in use such crane constructions present several well known disadvantages. Thus the crane structures are heavy, space consuming and quite expensive. A special problem arises frequently in connection with the total height of the crane structure, impeding the stability of the ship. Furthermore, such cranes to a large extent are exposed to the weather which naturally leads to corrosion and the risk of incidental malfunctions, due to failing bearings, cables and/or control equipment, etc.